Sayyiduna Abu Hurairah (may Allah be pleased with him) says that the Messenger of Allah (peace and blessings of Allah be upon him) appointed Siba’ bin ‘Arfatah (may Allah be pleased with him) as his deputy in Madinah and set out towards Khaybar. I migrated to Madinah and offered the Fajr prayer behind Siba’. In the first rak‘ah, he recited «كهيعص» (i.e., Surah Maryam), and in the second, «ويل للمطففين» (i.e., Surah Mutaffifin). Abu Hurairah (may Allah be pleased with him) says: (Upon hearing the recitation of Surah Mutaffifin) I began to say in the prayer itself,“So-and-so is ruined; he has made two kinds of measures: (that is) when he takes measure from others, he takes it in full, and when he gives measure to others, he gives less.”When we finished the prayer, we came to Siba’, and he prepared some provisions for our journey. (Then we set out towards the Messenger of Allah, peace and blessings of Allah be upon him) until we reached him. He had already conquered Khaybar. He spoke with the Muslims and included us in their (spoils) shares.